The use of relatively large visual displays at public events, such as sporting events, trade show and conventions, is well known. Signs that were changed by hand have been replaced by motor driven signs.
Scroll signs are one type of motor driven sign that has been use in applications, such as numbers for scoreboards. Existing scroll signs use a strip of web or film which is wrapped around two parallel rollers which can be oriented either vertically or horizontally. The display area is the area between the two rollers. As the rollers are rotated, the display is changed. Existing scroll signs have proven unsuitable for larger visual displays. Existing scroll signs have proven unable to maintain an undistorted visual image when the web or film containing the image has a larger size.
More recently, electronic signs have been used for visual displays at public events. The electronic signs have some advantages. They are typically computer contolled and can offer a sometimes dazzling variety of displays. Also, electronic signs have fewer moving mechanical parts, they may be less maintenance intensive than motor driven signs.
At the same time, there are several disadvantage with electronic signs. First, the visual quality of electronic signs is not particularly high. With electronic signs that use light bulbs for the visual display, the visual quality is crude. Even with the use of more advanced display elements such as LED's or large television-like displays, the quality of the image is not particularly high. Also, while electronic signs may have fewer mechanical parts, they frequently have a complex array of components, including computer controllers and software. Failure of a component can lead to the complete shut down of the display.
Another disadvantage of electronic signs, especially the larger types used at public events is that their complexity makes them extremely expensive to manufacture and purchase. Typically, they are installed only as permanent displays in large arenas, such as sports arenas or convention halls.
As illustrated by the above discussion there are a number of desirable features for a public display apparatus. It would be desirable for a public display apparatus to have a high quality visual image. It also would be desirable for a display apparatus to be reliable. In addition, it would be desirable for a public display apparatus to be economical to produce. Futher, it would desirable for a public display to be portable.
While the discussion herein relates to public display apparatuses and methods, it is not intended that the invention be limited to this situation. It will be obvious from the description that follows that the present invention will be useful in other applications with problems common to those described here.